Tetrahydropyrimidin-2-ones



United States Fatent O 3,236,848 TETRAHYDROPYRIMIDIN-Z-ONES Rudolf Merten, Cologne-Flittard, Germany, assignor is Farbenfabriken Bayer Aktiengesellschaft, Leverlrnseif, Germany, a corporation of Germany No Drawing. Original application Dec. 12, 1961, Ser. No. 158,905. Divided and this application Dec. 1, 1964, Ser. 'No. 415,187 Claims priority, application Germany, Dec. 19, 1960, F 32,789; Apr. 29, 1961, F 33,814; June 21, 1961,

6 Claims. (Cl. 260-251) This is a division of application Serial No. 158,905, filed December 12, 1961.

The present invention relates to the production of certain organic nitrogen bases by the hydrolyzing of compounds containing urethane groups and novel compounds obtained thereby. The compounds according to the invention are obtained by the condensation of (a) reaction products of carbamic acid esters with a'ldehydes or alkylidene diurethanes .in the presence of acidic catalysts with (b) cationic polymerisable monoand/ or polyolefines and any unsaturated compounds that react as dienes during a Diels-Alder reaction in the presence of theabove and/ or other acidic catalysts. The production of such condensation products is described in US. patent application Serial No. 143,044, filed October 5, 1961.

In accordance with the presence invention the novel organic nitrogen bases are defined by the formula IFIH in which X is a member of the group consisting of hydrogen, alkyl, aryl and carba'lkoxy radicals, R is a member of the group consisting of alkyl, cycloalkyl, aralkyl, aryl and a heterocyclic radical. For example, R may be a phenol, o-tolyl, p-tolyl, p-chlorophenyl, o-chlorophenyl, 2,6-dichloropheny l, 4-nitrophenyl, 2-acetoxyphenyl, hexyl, p-ani-syl, p-amin-ophenyl, o-n-itrophenyl, o-aminophenyl, cinnamyl, pynidyl, Z-methoxyphenyl, 2-acetoxyphenyl, isopropyl, 2-methoxy-3 -hydroxy-phenyl or a benzoyl radical. R is hydrogen, R" is a member of the group consisting of organic radicals represented by the formula R!!! JNH ill! and R'R" is represented by the formulae LIR III -(fiNHC- :RII!

III III III R R R and CHC=C in which R' is a member of the group consisting of the same or different hydrogen, halogen, alkyl, aralkyl, aryl alkoxy, and carbalkoxy radicals, wherein at least two radicals of the group R and R' are other than hydrogen and two radicals of the group R may be linked together through a polymethylene chain.

According to the hydrolyzing conditions used, there can be obtained from urethane derivatives of 1,3-diarnines, such as are obtained, for example, by the reactionv of mono-olefins with alkylidene-diurethanes according to the react-ion scheme given below, besides the corresponding ice amines I also the cyclic ureas 11 derived therefrom. Cyclic urethane derivatives III, such as can be obtained, for example, by the reaction of conjugated diolefines with alkylidene-diurethanes according to the above method, are converted by this hydrolyzing reaction into the amines IV. These reactions are reproduced substantially by the following reaction scheme:

The starting materials which come into consideration for the process of the present invention, i.e. the abovedefined condensation products, can be obtained by the methods of US. patent application, Serial No. 143,044, filed October 5, 1961.

Suitable aldehydes which serve as starting materials for the production of the above-mentioned condensation products are optionally monoor poly-functional, possibly substituted, aliphatic, cycloaliphatic, aromatic or heterocyclic types. As examples therefor, there may be mentioned: formaldehyde or formaldehyde yielding substances, such as, for example, trioxymethylene, paraformaldehyde, acetaldehyde, chloroacetaldehyde, trichloroacetaldehyde, propionaldehyde, 3-chloropropionaldehyde, butyraldehyde, isobutyraldehyde, oenanthaldehyde, steara ylaldehyde, glyoxal, benzaldehyde, alkyl-substituted benzaldehydes, such as p methyl benzaldehyde, methoxybenzaldehydes, such as anisaldehyde, halogenated benzaldehydes, such as 4-chloroor 2,6-dichlorobenzaldehyde, nitrobenzaldehydes, such as p-nitrobenzaldehyde, benZaldehyde-sulphonic acids, such as benzaldehyde-4- sulphonic acid, hydrogenated benzaldehydes, such as 4- methyl-hexahydr-obenzaldehyde, terephthalaldehyde, naphthaldehyde, phenyl-acetaldehyde, acrolein, crotonaldehyde, cinnamyl aldehyde, dialkylaminoacetaldehydes, dialkylaminobenzaldehydes, dimethylaminomethyl benzalaldehydes, pyridine-2-, pyridine-3- or pyridine-4-aldehyde or their substitution products, quiniline aldehydes, isoquinoline aldehydes, N-alkyl-indolaldehydes, furfurol, thiophenealdehyde, etc. Not only basic but also nonbasic aldehydes can here be used, whereby, in the case of basic aldehydes, these are reacted in the form of their salts with regard to the basic grouping.

As carbamic acid esters for the production of the starting materials are included any desired esters of unsubstituted carbamic acid of the general formula H N.COO-R', whereby R is any desired organic residue. As examples there may be mentioned: carbamic acid methyl ester, ethyl ester, propyl ester, butyl ester, isobutyl ester, hexyl ester, allyl ester, crotyl ester, benzyl ester, furfuryl ester, ,B-chloroethyl ester, B-dimethylaminoethyl ester, etc., whereby polyfunctional alcohols, such as ethylene glycol, butandiol-L4, glycerol or trimethylolpropane,

can be substituted wholly or partially for the production of the carbamic acid esters, for example, via a reaction of urea with the alcohol in question, a reaction of the corresponding chlorocarbonic acid ester with ammonia or by the partial aminolysis of a corresponding carbonic acid diester with ammonia.

As olefines for the production of the condensation products to be used within the meaning of the present invention, there can be used any desired monoor polyolefines which are accessible to a cationic polymerization. By way of example there may be mentioned straight chain or branched aliphatic olefines with 2-18 carbon atoms, such as ethylene, propylene, butylene, isohutylene, di-isobutylene or tri-isobutylene, cycloaliphatic types, such as vinylcyclohexane, aromatic substituted olefines, such as styrene, nuclearor side chain-halogenated styrenes, nuclearor side chain-alkylated styrenes, such as 'y-methyl-styrene, vinyl-pyridines, vinyl-quinolines, vinyl ethers, such as, for example, vinyl methyl ether, vinyl ethyl ether or vinyl butyl ether, as well as poly-olefines, such as butadiene- 1,3, isoprene, 2,3-dimethyl-butadiene, pentadiene, chloroprene, 2,3-dichloro-butadiene, Z-phenyl-butadiene, cyclopentadiene or dicyclopentadiene, 2-etl1oxy-3-methyl-butadiene, l-cyanobutadiene, Z-Cyanobutadiene, sorbic acid, vinyl-cyclohexene or divinylbenzene.

It is possible to employ as olefins during the preparation of the addition compounds to be saponified all those unsaturated compounds which can be used as dienes. Suitable examples of these compounds are given, for instance, in Neuere Methoden der praparativen organisohen chemie I (1943), pages 251-358, Chem. Reviews 31 (1942), page 319 et seq, etc. Among the large number of compounds there specified and also among the compounds described more recently and reacting as dienes, there may be mentioned: diene-hydrocarbons with a 1,3- diene structure, provided that they do not form the subject of the main patent owing to their polymerisability with cationic initiators, such as a-phelladrene, 1,1'-bicyclohexenyl, l,1-bicyclopentenyl, 1,1-bicyclobutenyl, 1-isopropenyl-cyclohexene, as well as their benzo-derivatives, etc., these being available, e.g., according to Z. obsc. chim. (1960) 2141-2145 and previous papers by mixed pinacoline reduction of ketones with aluminum amalgam and subsequent dehydration, 1,2-dimethylene-cycloalkanes and also their endo-substituted or/ and halogenated forms, e.g. according to British patent specification 796,133, British patent specification 796,135, J. Chem. Soc. 1960, pages 1541-1547, German specification 1,090,204, etc., and in addition also dienes such as furans, alkylfurans, cyclopentadienones, a,a,fi,fi-benzofuran. The diene system may also contain a hetero atom as a constituent, as is the case, e.g., in acrolein, vinyl-methyl ketone, o-methylenecyclohexanone, o-quinone-methidene, 2,2-bis-3-indolonyl (dehydro-indigo), and others. A further group of systems reacting as dienes is derived from the class of the polycyclic systems, which can be converted to higher conjugated systems, usually of an aromatic character, during the addition reaction. As examples there may be mentioned anthracene, alkyl and/or aryl substituted anthracenes, 2,3-benzanthracene, pentacene, methylcholanthrene, naphtho-2',3,3,4-pyrene, 1,9,5 1 O-diperinaphthylene-anthracene, 7,7'-dimethyl-(naphtho 2',3,1,2 anthracene), and others, also of thebaine, dihydropyridine, as well as of natural compounds such as derivatives of abietic acid, ergo sterines, etc.

The olefines used preferably contain agents stabilizing them against radical polymerisation, such as, for example, hydroquinone, phenothiazine, tert.-butyl-pyrocatechol and the like.

The alkylidene urethanes necessary for the production of the starting materials are produced in known manner (cf. Houben-Weyl, "Methoden der organischen Chemie, 7/1 (1954), page 481; 8 (1952), page 147) by the con densation of 2 mol of a carbamic acid ester with 1 mol of an aldehyde in an acidic medium. As acidic catalysts there come into consideration the substances mentioned in the following for the further condensation with olefines as well as any other desired acids, such as, for example, boric acid, acetic acid, hydrochloric acid, and the like.

Furthermore, there can also be used for the present process condensation products which are obtained by the condensation under other molar ratios of the components, i.e. particularly those ratios between 1:1 to 1:2 for aldehyde to carbamic acid ester.

These condensations can be placed immediately before the subsequent reaction with the olefine. In this case, the removal of the water formed is carried out, for example, by simple distillation or, preferably, by azeotropic distillation, for example, with the aid of a solvent, such as aliphatic hydrocarbons, cyclohexane or aromatics, etc.

Of course, alkylidene diurethanes produced in other ways can also be used for carrying out the present invention.

The production of the urethanes to be saponified takes place by the reaction of the alkylidene urethanes with the olefins in the presence of acidic catalysts, such as are known for the carrying out of Friedel-Crafts reactions. As examples there should be mentioned here: anhydrous organic and inorganic acids, such as sulphuric acid, phosphoric acid, perchloric acid, hydrogen halides, fluorosulphonic acid, chlorosulphonic acid, trichloroacetic acid, methane-sulphonic acid, toluene sulphonic acids, technical sulphonic acid mixtures of an aliphatic or aromatic nature, such as, for example, sulphonic acid-group containing long-chain parafiins with 10-18 carbon atoms, sulphonated polymers based on polystyrene, possibly cross-linked with polyvinyl compounds, or phenolformaldehyde condensates; furthermore, anhydrous metallic or non-metallic halides functioning as Lewis acids, such as boron tn'fluoride and its adducts with ether, acetic acid, etc., boron trichloride, phosphorus halides, phosphorus oxyhalides, aluminum chloride, zinc chloride, stannous and stannic chloride, ferric chloride, antimonic chloride, chromic chloride, and the like.

The proportions in the reaction of the olefines with the possibly intermediate formed alkylidene urethanes are widely variable. In the case of using equimolar amounts of alkylidene urethane and olefine, 1:1 adducts can hereby be obtained; however, in the case of using an excess of olefine also adducts with a higher proportion of olefine, while the use of excess alkylidene urethane is merely of interest for the complete conversion of the olefine used. Preferably there come into consideration ratios of the components which correspond to 1-10 equivalents of olefine per mol of alkylidene urethane grouping.

The amount of catalyst can also vary within wide limits, an upper limit being given by economic reasons, as well as, under circumstances, by difficulties arising in working up; normally, between 1 and percent by weight will be used but, nevertheless, the nature of the catalyst, of the reaction components, as well as the amount and nature of the solvent which may possibly be used, play an important part. In the case of using basic starting materials, these must be employed in the form of their salts. This is achieved most simply in that by the reaction, possibly even by the production of the alkylidene urethanes, at least one equivalent of an acidic substance, preferably from the group of the catalysts mentioned, is added per equivalent of the basic compound.

For the carrying out of the addition reaction, the alkylidene urethane, which can also be produced directly in a previous operation in anhydrous form in the presence of an acidic catalyst for subsequent use or also in a weak acid, is present normally under the most anhydrous conditions possible. In this case, the most varied, preferably non-polar solvents, such as aliphatic hydrocarbons, benzene, toluene, xylene, cyclohexane and the like, can be added. After the addition of the catalyst, the olefine is then added, whereby in the case of low boiling olefines one can also work under pressure, preferably under the actual pressure of the olefine used. After the addition of the olefine, the addition is carried out to the end, possibly at an elevated temperature, whereby the alteration of the refractive index, for example, is used for the control of the course of the reaction. As temperatures for the addition of the olefine and the post-reaction periods, there generally come into question temperatures between 40 C. and +l80 C., the reactivity of the components being of important influence. On the other hand, the nature of the addition can also be varied in that, for example, the diurethane and the olefine can be added dropwise to the catalyst or, in less reactive cases, the catalyst can also be added dropwise to the reaction mixture; however, in all cases, the direct prior contact between the olefine and the acidic catalyst is to be avoided. The working up of the addition products takesplace in known manner in that, for example, after removal of the acidic catalyst, unreacted starting substances and by-prodnets are washed out or removed by distillation.

In the addition step it is, of course, possible, to use instead of the individual definite olefins, aldehyde, carbamic acid esters or catalysts, also mixtures thereof.

The so-obtained addition products are obtained in high yields and are liquid or solid, generally well soluble products. As by-products there can appear in minor amounts dimeric olefines, cyclic condensates of olefine and aldehyde with m-dioxan structure or also Friedel-Crafts adducts.

According to the process of the present invention, the condensation products obtained in the above-described manner from' (a) reaction products produced from carbamic acid esters with aldehydes in the presence of acidic catalysts or alkylidene diurethanes and (b) cationic polymer-isable monoand/or polyolefines in thepresence of the above and/or other acidic catalysts, are subjected to a saponification reaction. The carrying out of the saponification can take place at any desired pH value, not only in alkaline but also in neutral and acidic medium.

As saponification agents therecan be used, for example, the most varied basic. substances, such as, for example, alkali metal hydroxides, such as LiOH, NaOH, KOH, alkaline earth metal oxides, such as Ca(OH) MgO, MgCO Ba(OH) as well as K 00 NH or NH OH and the like. Furthermore, it is also possible to use strong organic bases, such as, for example, quaternary ammonium bases, such as benzyl-trimethyl ammonium hydroxide and tertiary sulphonium bases. Fundamentally, any desired large amountsof these bases can be used but preferably amounts of about 0.1-3 mol equivalents of base per urethane grouping come into consideration.

In the case of acidic saponification, there are possibly only used catalytic amounts of any desired acid, preferably, however, at least an amount of acidequivalent to the theoretically expected amount of amine. Examples of acids which are suitable for this saponification reaction are HCl, HBr, H 80 H PO H BO as well as strongly acidic and also weakly acidic (sulphonic acid or carboxylic acid group-containing ion exchangers), carbon dioxide, as well as' organic acids, such as, for example, acetic acid, trichloroacetic acid, p-toluene-sulphonic acid, benzene-sulphonic' acid and the like.

Furthermore, it is also possible to effect the. saponification in a neutral medium, for example with water at elevated temperatures, i.e., 100-250 C., under pressure.

The reaction medium can be of an aqueous or alcoholic as well as of an aqueous-alcoholic nature. As alcoholic reaction media there may be mentioned methanol,

ethanol, glycol, glycol monobutyl ether (Cellosolve) or tions have proved to be expedient for the avoidance of this urea formation. At loWer temperatures and/ or acidic saponification conditions, the equilibrium is displaced in favour of larger amounts of urea. The time for the saponifi'cation depends on the temperature and reaction medium; it preferably lies between 1 and 20 hours. According to a preferred embodiment of the present invention, it is also possible previously to subject the products to be saponified to a modification. For example, nitro groups can be reduced and carbon-carbon double bonds can be saturated by hydrogenation.

After carrying out the saponification, which can possibly be carried out under pressure, the amine obtained can either be separated directly from the basic reaction solution, for example, by extraction with solvents, such as aromatic, aliphatic, cycloaliphatic or halogenated hydrocarbons or ethers, and distilled. On the other hand, it is also possible first to purify the amine via an intermediate salt formation or, according to the properties, to isolate it directly as crude salt with the help of the most varied acids, such as HCl, H HCIO or picric acid. Acidic reaction solutions are preferably first freed from impurities soluble in organic solvents, such as benzene, by extraction and the reaction product, after alkaline adjustment of the reaction solution, isolated as free amine or isolated as amine salt from acidic solution.

The amines obtainable according to the process of the present invention are suitable in the form of their salts as emulsifiers or dispersing agents. The primary amines obtained by this process or the polyamines derived from these amines can also serve as intermediates for the production of the most varied products, for example, for the production of polyisocyanates, while the pyridine derivatives obtained with conjugated diolefines can be used as intermediates for the production of piperidine or pyridine derivatives.

The inventively obtained compounds are insecticides and show a good activity, whereas their mammalv toxicity is low. They therefore may be applied for the combating of insects, especially for the combating of flies and mosquito larvae.

New compounds according to the present invention can be in particular characterized by the formula wherein X is hydrogen, R is a member selected from the group consisting of hydrogen, phenyl, p-tolyl, p-chlorophenyl, o-chlorophenyl, 2,6-dichlorophenyl, 4-nitrophenyl and 2-acetoxyphenyl, R' (shown below) is a member selected from the group consisting of hydrogen, methyl and phenyl while R'R stands for Expressed differently these compounds can be characterized as follows:

f Ill-43 $R2 1|\TH NH C II 0 wherein R is defined as above while R and R conform to the definition of R' above. More particularly R can stand for hydrogen, phenyl, p-tolyl, dichlorophenyl and monochlorophenyl, R for hydrogen and R for phenyl in the above formula.

The following examples illustrate the described process. The parts given are parts by weight insofar not otherwise stated.

Example 1 (a) 106 parts of benzaldehyde, 178 parts of carbamic acid ethyl ester, 2.5 parts of BF -ethe'rate and 700 parts of benzene are heated to boiling under reflux until the azeotropic splitting off of water hereby effected with the help of a water trap is ended. A further 25 parts of BF etherate are then added and, while excluding moisture, 104 parts of styrene added dropwise at 90 C. in the course of about 4 hours. A temperature of 90120 C. is maintained for about 15 hours while a part of the benzene distills off, then the mixture allowed to cool, the acidic catalyst is washed out With dilute soda lye, the aqueous phase separated off and the organic phase is freed from liquid by-products, starting materials etc. by distillation at 160 C./ 0.1 mm. Hg. As residue there remains about 350 parts of the viscous, resin-like bis-urethane with 7.35% N (theoretical: 370 parts bis-urethane with 7.7% N).

(b) 350 parts of the bis-urethane obtained according to (a) are, after flushing with nitrogen, heated in an autoclave for 4 hours at 230 C. with 300 parts of ethanol and a solution of 215 parts solid KOH in 215 parts water or 430 parts of 50% technical KOH. After cooling, the amine is separated from the aqueous phase with about 200 par-ts of benzene. For the purposes of purification, the benzene phase is then again extracted with 25% hydrochloric acid and the amine subsequently separated out from the aqueous hydrochloric acid phase in the form of a viscous oil by the addition of alkali. The free amine is taken up with benzene and distilled in a vacuum. After small first runnings, there are obtained about 120 parts amine I with a boiling point of 140170 C./0.1 mm. Hg, as well as 15 parts of higher, homologous amine II with a boiling point of 170200 C./0.l mm. Hg.

By redistillation of amine I, there is obtained 1,3-diphenyl-1,3-diamino-propane with a RP. of 135 C./0.07 mm. Hg and a n =1.5836.

Calc. C H N 79.6% C, 8.0% H, 12.4% N Found: 79.4% C, 8.0% H, 12.5% N

(c) 357 parts of the bis-urethane obtained according to (1a) are melted and 280 parts KOH in 150 parts of water slowly introduced at about 100 C. With continuous distilling off of water and ethanol, it is heated to 250 C., maintained for 3 hours at 250 C. and the mixture of amine and lye then worked up in the manner described under (1b). 80 parts of the amine mixture there described under I are thereby obtained.

(d) 4.5 parts of the diamine according to (1b) are concentrated on the water bath with excess conc. hydrochloric acid, stirred up several times with ethanol and finally recrystallized from ethanol/acetone. The bishydrochloride of 1,3-diphenyl-1,3-diamino-propane melts at about 340 with decomposition.

Calc. C H N Cl 60.2% C, 6.7% H, 9.4% N, 23.7% C1 Found: 60.0% C, 6.9% H, 9.4% N, 23.5% C1 (e) 100 parts of the diamine obtained according to (1b) are dissolved in 500 parts of chlorobenzene and then added dropwise below C. to a solution of 350 parts phosgene in 100 parts of chlorobenzene. A fine suspension is formed which becomes clear by heating to about 100 C. Phosgenation with 700 parts phosgene for a further 4 hours under reflux takes place, subsequently, phosgene expelled by nitrogen at an elevated temperature and the product dis-tilled in a vacuum. The so-obtained 1,3-diphenyl-propane-1,3-diisocyanate boils at 150155 C./0.05-0.07 mm. Hg, n =l.5650.

Calc. C H N O 73.4% C, 5.1% H, 11.5% 0, 10.1% N Found: 73.8% C, 5.3% H, 11.2% 0, 9.6% N, 0.4% Cl Example 2 74 parts of the condensation product obtained according to Example la are heated to boiling under reflux for 15 hours with 56 parts KOH and 300 parts n-butanol, the butanol is substantially removed in a vacuum and the residue taken up in half conc. hydrochloric acid. There remain behind I about 16 parts of an insoluble product which, after recrystallization from ethanol, melts at 265 C. and is 4,6-diphenyl-Z-oxo-hexahydropyrimidine.

Calc. C H N O: 76.2% C, 6.4% H, 11.1% N, 6.3% 0 Found: 76.3% C, 6.5% H, 11.2% N, 6.5% O

The hydrochloric acid phase is rendered alkaline with KOH and, after being taken up with benzene, gives upon distillation 30 parts of the 1,3-diphenyl- 1,3 -diaminopropane described in Example 1b. The urea I can similarly be converted into the above amine by saponification with KOH at 230 C.

Example 3 (a) 100 parts of paraformaldehyde, 450 parts of carbamic acid methyl ester, 10 parts of conc. sulphuric acid and 1000 parts of benzene are heated to boiling under reflux until the azeotropic splitting ofi of 'water hereby effected with the help of a water trap is ended. Subsequently, a further 50 parts of sulphuric acid are added and at C. 312 parts of styrene added dropwise Within 4 hours. The mixture is heated for 15 hours at 90l00 C., the acidic catalyst washed out with dilute alkali and there is obtained, upon concentration at 160 C./l2 mm. Hg, a total of 689 parts of the corre-' sponding diurethane with 9.8% N (calc. for 1:1 adduct: 10.5% N).

(b) 667 parts of the condensation product produced according to (3a) are dissolved in 600 parts of ethanol and a solution of 650 parts KOH in 800 parts of water added. The mixture is heated for 4 hours at 230 C. and then worked up in the manner described under (1b), whereby the amine is finally extracted with ether. The distillation gives 130 parts of a mixture of homologous amines at 7096 C./0.2 mm. Hg with 73.9% C, 9.25% H, 14.5% N, while there is calculated for 1-pheny1-1,3-diaminopropane 72.0% C, 9.4% H and 18.7% N.

Example 4 200 parts of the addition product obtained according to Example 3a are dissolved in 300 parts of ethanol, parts of water are added and heated for 4 hours at 230 C. in an autoclave pressurized to 60 ats. with CO After cooling, about 70 parts of the 4-phenyl-2-oxo-hexahydropyrimidine are filtered off which, after recrystallization from ethanol, melts at 237-238 C.

Calc. C H N O2 68.2% C, 6.9% H, 15.9% N Found: 68.1% C, 7.0% H, 15.9% N

The filtrate is worked up in the manner described in Example 3b and gives about 40 parts of the homologous amine mixture described therein.

The saponification can also be carried out in the abovedescribed manner with the use of 1% phosphoric acid as catalyst and leads to practically the same result.

Example 5 (a) 240 parts of p-tolyl aldehyde, 300 parts of carbamic acid methyl ester, 400 parts of benzene and 2 parts of BF -etherate are first converted in the manner described in Example 1b, with 2 parts of BF -etherate into the alkylidene-bis-urethane and then, after the addition of a further 40 parts of BF -etherate, added at 90-100" C., to 208 parts of styrene. After analogous working up, there is obtained the addition product in a yield of 550 parts.

Found: 70.4% C, 6.9% H, 7.1% N; calc. for 1:1 adduct:

67.9% C, 6.8% H, and 7.9% N

(b) 488 parts of the adduct produced as above are, after dissolving in 500 parts methanol, heated in an autoclave, together with 168 parts KOH and 450 parts of water, for 10 hours at 240 C. and the reaction mixture acidified after cooling. Thereby precipitate out I 37 parts of the cyclic urea. The 4-phenyl-6-p-tolyl-2- oxo-hexahydropyrimidine is recrystallized from ethanol and melts at 234--235 C.

Calc. c n N o; 76.6% c, 6.8% H, 10.5% N, 6.0% Found: 75.9% c, 7.0% H, 10.0% N, 6.1% o

The acidic solution is subsequently rendered alkaline, taken up in benzene and distilled whereby II the l-phenyl- 3-p-tolyl-1,3-diamino-propane goes over at 164165 C./ 0.1 mm. Hg with n =1.5798.

Calc. CIGHZONZI C, H, N Found: 79.9% C, 8.3% H, 11.5% N

Example 6 650 parts of a crude bis-(N-carbethoxy)-diamine produced according to Example a with carbamic acid ethyl ester are dissolved in 600 parts of ethanol, 450 parts KOH in 600 parts of water added and, after flushing with nitrogen, heated for 4 hours at 230 C. As main fraction are obtained, after working up the amine in analogy to Example 1a, 178 parts of the 1-phenyl-3-p-tolyl-1,3-diaminopropane described in more detail in Example 5b under II.

1' Example 7 (a) 178 parts of carbamic acid ethyl ester, 175 parts of 2,6-dichlorobenzaldehyde, 400 parts of benzene and 3 parts of BF -etherate are converted analogously to Example 12. into the alkylidene-diurethane and, after the addition of parts of BF -etherate, added to 104 parts of styrene. With analogous working up, the crude bisurethane with. a yield of 380 parts is obtained.

CHIC. for 121 adduct C21H24N2C1204: C, H,

6.4% N, 16.1% C1, 14.6% 0 Found: 57.6% C, 5.3% H, 5.6% N, 18.3% Cl (b) 200 parts of the addition product obtained according to Example 7a are heated to 230 C. With 300 parts of ethanol, 100 parts of Water and 2 parts of phosphoric acid for 6 hours and a solid material filtered oif from the reaction product. This was recrystallized from ethanol and gave 4-phenyl-6-(2',6'-dichlorophenyl)-2-oxo-hexahydropyrimidine in a yield of parts with an M.P.- of 278-280 C.

Calc. CmHmNgOClgl N, Found: 9.0% N, 21.6% C1 The filtrate of the cyclic urea is concentrated, whereby 117 parts of a non-crystallizing material are obtained which, according to the infra-red spectrum, is a linear amino-urea.

Example 8 380 parts of an addition product obtained according to Example 7a are heated for 4 hours at 230 C. with 500 parts of ethanol, 225 parts KOH and 400 parts of water, after cooling taken up with benzene and, after separation of the aqueous phase, extracted with half conc. hydrochloric acid. By concentration on the water bath and repeated trituration with ethanol, a semi-crystalline mass is obtained in an amount of 123 parts, the infra-red spectrum of which with regard to the functional groups is identical with the spectrum of the 1,3-diamino- 1,3-diphenylpropane dihydrochloride obtained according to Example ld. The broadening of the bands at 13 indicates the vicinal tri-substituted aromatics. For a dihydrochloride of 1 phenyl 3 (2',6' dichlorophenyl) 1,3-diaminopropane there is calculated: C H N Cl 7.6% N, 38.5% Cl, found 6.2% N, 28.1% C1.

Example 9 (a) 228 parts of heptyl aldehyde, 356 parts of carbamic acid ethyl ester, 5 parts of BF -etherate and 800 parts of benzene are converted analogously to Example 1a into the alkylidene-diurethane and, after the addition 10 of 50 parts of BF -etherate, this is added at C. to 208 parts styrene. By analogous working up, 309 parts of the crude urethane are obtained with 73.2% C, 10.4% H, and 5.2% N, whereas there is calculated for a 1:1 adduct 66.6% C, 9.1% H and 7.4% N.

(b) 302 parts of the condensation product obtained according to (a) are dissolved in 300 parts of ethanol, 200 parts KOH in 200 parts of water are added and heated for 4 hours at 230 C. After distilling off. the ethanol, the residue is extracted at a pH value of 12 with benzene and the benzene phase subjected to distillation. Thereby 88 parts of a crude amine go over with a boiling point of l80 C./0.1 mm. Hg which shows 4.4% nitrogen and a refractive index n ":1.4880.

The infra-red spectrum of the distillate shows no difference in comparison with the spectrum of the diamine obtained according to Example 3b with regard to the position of the functional groups. The higher proportion of aliphatics appears very clearly in an accentuation of the aliphatic CH oscillations.

Example 10 (a) 280 parts of p-chlorobenzaldehyde, 356 parts of carbamic acid ethyl ester, parts of a polystyrene sulphonic acid cross-linked with 2% divinyl-benzene and 800 parts of benzene are heated to boiling under reflux until the azeotropic splitting ofl? of Water hereby effected with the help of a water trap is ended and 208 parts of styrene then added dropwise at 80 C. The mixture is heated for 20 hours at 80120 C. this temperature being reached by distilling off a corresponding amount of benzene. The acidic catalyst is removed by filtration and the crude urethane freed from solvents and liquid components by distillation up to 150 C./ 12 mm. Hg. There is obtained, in a yield of 620 parts, an addition product with 5.9% N and 10.85% Cl, while there is calculated for a pure 1:1 adduct 6.9% N and 8.8% Cl.

(b) 293 parts of the addition product produced as described above are dissolved in 300 parts'of ethanol and heated for 4 hours at 230 C. in an autoclave together with 225 parts KOH and 300 parts of water. After taking up the reaction product in about 200 parts of benzene, the alkaline aqueous phase is separated off and the benzene phase extracted with half concentrated hydrochloric acid. Upon concentration of the hydrochloric acid phase, the hydrochloride, which is moderately soluble in Water, precipitates out in the form of white crystals which melt at 302306 C. The yield amounts to about 70%.

Calc. for 1-phenyl-3-p-chlorophenyl-1,3-diaminopropane dihydrochloride C H N Cl 8.4% N, 31.9% C1 Found: 7.9% N, 30.0% C1 The infra-red spectrum is, with regard to the functional groups, practically identical with the spectrum of the dihydrochloride obtained according to Example 1d. The p-substituted benzene nucleus appears additionally by the band 12.05 1.

(c) By the saponification according to Example 10b with heating under reflux, there is obtained, with analogous working up, the there described dihydrochloride in a yield of about 30%. In addition, White needles are obtained in an amount of 30 parts which are 4-phenyl-6- (4'-chlorophenyl) 2 0x0 hexahydropyrimidine and are recrystallized from ethanol.

M.P. 249 C.:

Calc. C H N OCl: 9.8% N, 12.4% 01 Found: 9.9% N, 12.4% C1 Example 11 (a) 266 parts of benzal-diurethane and 60 parts of BF -etherate are mixed in 500 parts absolute benzene at 60 C. in the course of 4 hours with 520 parts of styrene and subsequently stirred for 10 hours at 60 C., whereby the refractive index alters from 1.5230 to 1.5285. The

acidic catalyst is then washed out with sodium bicarbonate solution and the product freed from solvents and liquid components up to 120 C./0.1 mm. Hg. The crude urethane is thereby obtained in a yield of about 590 parts. The product shows a nitrogen content of 4.4% and an oxygen content of 9.8% which corresponds to the addition of an average of 3.8 mol styrene to 1 mol benzal-diurethane.

(b) 200 parts of the addition product described under (a) are heated for 6 hours at 230 C. with 300 parts of ethanol, 100 parts of water and 2 parts of phosphoric acid and the semi-solid mass then separated by filtration. The solid residue consists preponderantly of the 4,6-diphenyl- 2-oxo-hexahydropyrimidine described in Example 2. Upon concentration, the filtrate yields 42 parts of a polymeric amine with 5.0% N which, according to the intrared spectrum, is substantially identical with the amine described in Example 1b. Only the frequencies ascribable to the aromatic components are strengthened.

Example 12 (a) 177 parts of p-diethylaminobenzaldehyde, 178 parts of carbamic acid ethyl ester and 800 parts of benzene are treated dropwise at room temperature with 100 parts of cone. sulphuric acid and the mixture heated to boiling until the end of the azeotropic removal of water. A further 30 parts of cone. sulphuric acid are then added and 104 parts of styrene added dropwise at 8090 C. The mixture is heated for 15 hours 90l20 C. and then the acid present neutralised with dilute soda lye. The benzene phase is separated off at pH 7-8 and the crude condensate freed from volatile components up to 160 C./ 0.1 mm. Hg.

Calc. for 1:1 adductC H N O 68.1% C, 8.0% H,

9.5% N Found: 73.8% C, 7.7 H, 7.9% N

(b) 295 parts of the adducts obtained as described above are heated for 4 hours at 230 C. with 350 parts of ethanol, 200 parts KOH and 200 parts of water, the ethanol distilled off and, after cooling, the aqueous phase shaken out with benzene. The benzene phase is then treated with half dilute HCl and the separated hydrochloride concentrated on the water bath. After repeated trituration with ethanol, the hydrochloride is obtained as a semi-solid mass in an amount of 150 parts. The infra-red spectrum of the hydrochloride shows, with regard to the functional groups, substantial similarity with the dihydrochloride obtained according to Example 1d. The p-substituted aromatic nucleus is additionally recognizable by a band at 11.9 Due to the different nature of the amine salt groups, a clear split of the salt bands occurs in the region between 3 and 4,1.

Example 13 (a) 50 parts of p-dimenthylaminobenzaldehyde, 60 parts of carbamic acid ethyl ester and parts of conc. sulphuric acid are reacted, analogously to Example 12a,

initially with 200 parts benzene to the corresponding alkylidene urethane and then, after the addition of a further 10 parts of cone. sulfuric acid, in the way there described with 35 parts of styrene to give, after corresponding working up, 104 parts of the crude urethane with 8.3% N.

(b) parts of the adduct described under (a) are heated for 4 hours at 230 C. with 200 parts of ethanol, 70 parts KOH and parts of water, after cooling taken up with benzene and concentrated, whereby the crude amine is obtained in an amount of about 70 parts. This was taken up with conc. hydrochloric acid, organic impurities removed by shaking out with benzene and the hydrochloride concentrated on the water bath. There 83 parts of a semi-crystalline mass remain which melt at about 312 C. with decomposition.

Found 6.8% N, 17.05% Cl; for l-phenyl-3-p-dimethylaminophenyl-l,3-diaminopropane trihydrochloride there is calculated 11.1% N and 28.1% C1.

The infra-red spectrum of the salt is practically identical with the spectrum of the salt obtained according to Example 12b. In the skeletal range of the spectrum, a few slight deviations occur.

What I claim is:

1. An organic nitrogen base of the formula wherein R stands for a member selected from the group consisting of hydrogen, phenyl, p-tolyl, p-chlorophenyl, o-chlorophenyl, 2,6-dichlorophenyl, 4-nitrophenyl and 2- acetoxyphenyl, R stands for phenyl and R stands for a member selected from the group consisting of hydrogen, methyl and phenyl.

2. The organic nitrogen base of claim 1 wherein R and R stand for phenyl and R stands for hydrogen.

3. The organic nitrogen base of claim 1 wherein R and R stand for hydrogen and R stands for phenyl.

4. The organic nitrogen base of claim 1 wherein R stands for p-tolyl, R stands for phenyl and R stands for hydrogen.

5. The organic nitrogen base of claim 1 wherein R stands for 2,6-dichlorophenyl, R stands for phenyl and R stands for hydrogen.

6. The organic nitrogen base of claim 1 wherein R stands for p-chlorophenyl, R stands for phenyl and R stands for hydrogen.

References Cited by the Examiner McKay et al.: J. Amer. Chem. Soc., vol. 71 (1949), pages 76670.

IRVING MARCUS, Primary Examiner.

NICHOLAS S, RIZZO, Examiner. 

1. AN ORGANIC NITROGEN BASE OF THE FORMULA 